Start with the noodles, which need to be prepared 8-12 hours before serving, since they need to be dried. Put the flour in a bowl and wisk in the baking powder. Add water and keep stirring and then kneading the flour until you get a pliant dough. Break off a ball of dough, and spread it to get a very thin sheet. Flour this sheet generously, then roll it into a tubular shape, then put aside to dry. Do the same with the rest of the dough. After an hour or so, take the rolls of dough and make cuts all the way across with a sharp knife. The strips thus cut should unfold easily, giving the noodles. Let the noodles stand for about 8 hours (overnight, for example). About three hours in advance, begin the broth. Put all the broth ingredients except the oil, the bouillon, salt and pepper, and parsley together in a stock pot, and bring to a boil. Then lower the heat and simmer for about another half an hour. Remove all the vegetables except for the carrots and potatoes, and strain the broth as well as possible. Put back on the stove, and add the bouillon and the oil and stir well. Add salt and pepper to taste. Then put in the noodles, bring to another boil, and keep on the heat until the noodles are soft. Top with chopped parsley and serve, giving each person a piece of carrot or potato if wanted.